US2620976A - Mechanism for converting pence amounts to sterling - Google Patents

Mechanism for converting pence amounts to sterling Download PDF

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US2620976A
US2620976A US188431A US18843150A US2620976A US 2620976 A US2620976 A US 2620976A US 188431 A US188431 A US 188431A US 18843150 A US18843150 A US 18843150A US 2620976 A US2620976 A US 2620976A
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contacts
relay
accumulator
value
segment
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Albert J Keen
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International Business Machines Corp
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    • GPHYSICS
    • G06COMPUTING; CALCULATING; COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F7/00Methods or arrangements for processing data by operating upon the order or content of the data handled
    • G06F7/38Methods or arrangements for performing computations using exclusively denominational number representation, e.g. using binary, ternary, decimal representation
    • G06F7/46Methods or arrangements for performing computations using exclusively denominational number representation, e.g. using binary, ternary, decimal representation using electromechanical counter-type accumulators
    • G06F7/462Multiplying; dividing

Description

Dec. 9, 1952 K I 2,620,976
MECHANISM FOR CONVERTING FENCE AMOUNTS TO STERLING Filed ed. 4, 1950 a Sheets-Sheet 1 ACCUMULATOR COMMUTATORS UNITS A 0R MAGNETS umTs R10 R16 R15) INVENTO ALBERT J KN FIGJ.
ATTORNEY Dec. 9, 1952 A. J. KEEN 2,620,975
MECHANISM FOR CONVERTING FENCE AMOUNTS TO STERLING Filed Oct. 4, 1950 a Sheefs-Sheet 2 TEN THDU TEN THOU B me R5 0 SENSING COMMUTATQR INVENTOR ALBERT J KEEN ATTORNEY Riel Dec. 9, 1952 A. J. KEEN 2,620,976
MECHANISM FOR CONVERTING FENCE] AMOUNTS TO STERLING Filed Oct. 4,1950 3 Sheets-Sheet 3 FIG. lb.
ACCU MU LATO R COM MU TATORS UNtTS D 7 UNITS R34 FENCE wNUIU' smLL's INVENTOR ALBERT J KEEN ATTORNEY Patented Dec. 9
MECHANISM FOR CONVERTING PENCE AMOUNTS T STERLING Albert J. Keen, Letchworth, England, assignor to International Business Machines Corporation, New York, N. Y., a corporation of New York Application October 4, 1950, Serial No. 188,431
. In Great Britain October 12, 1949 10 Claims. 1
This invention relates to means for translating amounts expressed in pence into the equivalent sterling amount and it is more particularly directed to such translatingmeans suitable for use with record card controlled multiplying and dividing machines.
Record card controlled machines operating in the decimal notation may b utilized for problems involving a sterling multiplicand by first converting the sterling value to pence. When the calculation has been completed, it is necessary to re-convert the answer frompence to sterling. It will be appreciated that if part of the equipment already available in the decimal multiplier may be used in the reconversion, the cost and complexity of the extra equipment required to enable the decimal multiplier to deal with sterling will be appreciably reduced.
Accordingly, it is an object of the present invention to provide translating means to enable a product or quotient expressed in pence, calculated by a record card controlled multiplying or dividing machine, to be converted to the equivalent sterling value.
According to the inventioma device for translating a value in pence expressed in decimal notation in an accumulator into sterling notation comprises an accumulator having read out commutators and electrical circuit dividing networks whereby one sixth the value registered on the accumulator, neglecting any remainder, may be combined with the said value so that the said accumulator registers the five sixths value correctly in the tens and higher denominations, and also a further dividing network whereby half the said five sixths value as registered in the hundreds and higher denominations may be read out as the units and higher denominations of pounds respectively.
Other objects of the invention will be pointed out in the following description and claims and illustrated in the accompanying drawings, which disclose, by way of examples, the principle of the invention and the best mode, which has been contemplated, of applying that principle.
In the drawings:
Figs. 1, 1a and lb placed one beneath the other comprise a circuit diagram of the preferred form of translator.
It will be appreciated that the translating means of the invention may be used inconjunction with various types of record card controlled multiplying and dividing machines; however, by
way of example, it will be described'as applied'to a machine of the type disclosed in the patent 2 to J. W. Bryce et al., No. 2,328,610 dated September 7, 1943. r i
The translation of 2, pence value to sterling may be considered as consisting of three stages:
(1). Division by 240 to obtain a whole number of pounds,
(2). Division of the remainder of (l) by 12 to obtain a whole number of shillings,
(3). The remainder from (2) comprises the number of pence. f
This direct method of translation is not easily effected on a multiplier ofthe type shown in the reference patent and accordingly the method is modified in the following manner.
(1) Divide the pence amount p by six to form a whole number quotient and a remainder r.
(2). Subtract the quotient by two and column shift the resulting quotient downwards two places to give the whole number of pounds and a remainder s.
The result of these three operations is to efiect from p to form a division by 240 as is shown by the identities: 3. l i i( 2) 240* 6 2005200 p 6 Due to neglecting the remainder r the value of may b in error by an amount not greater than live and this is insufficient to cause an error in either the pounds or shillings values.
If the hundreds digit of the value is odd, then the final sterling value must contain a shillings term of ten or greater and accordingly any odd number in the hundreds denomination controls the reading out oflone in the tens of shillings denomination.
B 2 (p or 6 so that if this remainder is divided by ten, the whole number resulting will be one twelfth of the original pence value registered in the units and tens denominations. Thus the digit registered in the tens denomination of may be read out directly as the units of shillings digit.
To obtain the pence value of the sterling result it is necessary to take into account the remainder r and Whether the units digit of is odd or even. The first case is when the quotient has an even units digit and 1' is 5 or less. If six is divided into any number which gives an even quotient less than 10 and no remainder, then the quotient digit and the units digit of the dividend are the same.
Thus when the one sixth quotient is subtracted from the dividend the units figure of the result will be zero. than zero, then the units figure of the result will be the same as the remainder. For example:
13:6=2+l reminder In this case if the quotient digit is subtracted from the dividend the units digit of the result is one less than the correct pence value. Accordingly an odd quotients digit is decreased by one before subtracting the. quotient digit from the dividend. For example:
18 pence=ls. 6d.
45 pence=3s. 9d.
Similarly if the remainder is other The third case arises when the units digit of the quotient is odd and the remainder 1' is 4 or 5. The pence value Will then be tenpence or elevenpence and since the accumulator is operating in decimal, special provision has to be made for reading out these values. When there is an odd units digit and the remainder is 4, a relay is operated to record this fact and to control the reading out of tenpence, and if the remainder is 5, a second relay is operated which controls the reading out of elevenpence.
Certain of the contacts of these relays are so connected in the dividing circuit that, whether the remainder be four or five, the units digit resulting after subtraction is 9. To effect this, when the original value is such as to give a final read out of tenpence, the contacts of the first relay suppress the subtraction of one from the quotient and when the read out is elevenpence, the second relay is also operated and serves to suppress the elusive one carry which arises during subtraction by complemental addition and thus, in effect, increases the quotient value by one.
It will be assumed that at the end of the multiplying or other calculation the result in pence is contained in a single accumulator which may well be the usual products accumulator. The accumulator is shown as consisting of five denominations, and may be of the type shown in the reference patent. Each denomination is provided with five readout commutators of the type shown in the reference patent, which are referenced A, B, C, D and E. However, in the units denomination commutators C and E are not used and in the tens denomination commutator E is not used. Therefore these commutators are not shown in the drawings.
The common bars of the accumulator commutators A and B for each denomination are connected to a corresponding segment of the sensing commutator (Fig. 1a). The brush 2 of this commutator successively connects the segments to the common bar 1, commencing with segment IS, the commutator brush being secured to a shaft which is driven from the main driving shaft of the machine through suitable gearing. Thus the A and B accumulator commutators of each denomination are connected to the common bar I each denomination successively commencing with the highest denomination.
By way of example it will be assumed that the pence value standing on the accumulator at the commencement of the conversion operation is 16307.
At the beginning of the first machine cycle of conversion, the relay RH (Fig. 1a) is energized. This may be efiected, for example, by the closure of cam contacts operated by a cam shaft driven by the machine or by a similar means which is operated when the multiplication is completed. The closure of contacts RI a connects the common bar I of the sensing commutator to line I through the circuit breakers CB and contacts RI la.
After the energization of relay RH the brush 2 of the sensing commutator commences to move successively over the segments I6, l5, M etc. of the commutator. When the brush 2 reaches segment 5 a circuit is completed as follows: line 1 (Fig. 1a), contacts RI Ia (closed), circuit breakers CB, common bar I, brush 2, segment 5, commutator common bar A of the ten thousands denomination, segment I, relay R2I to line 6, lines 6 and I being the two main supply lines, thus energizing relay R2I and also relay R21 via contacts R2 Iq. The common bar of commutator A will be connected to segment I since the value I is registered in this particular denomination.
As the sensing commutator brush 2 moves successively over the remaining segments further circuits will be made from line I in similar manner. I
(1). From segment 4, commutator common bar A of the thousands denomination segment 6, f contacts of relay R2I (shifted), e contacts of relay R22 (normal), relay RI8 to line 6, thus energizing relay RIO and also relay R26 via contacts RI.
(2). From segment 4, commutator common bar B of the thousands denomination, segment 6, e contacts of relay R2I (shifted), relay R20 to line 6, thus energizing relay R20.
(3). From segment 3, commutator common bar A of the hundreds denomination (Fig. 1) segment 3, f contacts of relay RI 6 (shifted), e contacts of relay RIO (normal), relay RI5 to line 6, thus energizing relay RI5 and also relay R25 (Fig. 1a) via contacts RI Sq.
(4). From segment 2, commutator common bar A of the tens denomination, segment 0, f contacts of relay RI5 (shifted), e contacts of relay RI6 (normal), relay RI2 to line 6, thus energizing relay RI2 and also relay R24 (Fig. 1a) through contacts Rl2q.
(5). From segment 2, commutator common bar B of the tens denomination, segment 0, e contacts of relay RI5 (shifted), relay RI4 to line 6, thus energizing relay RI4.
(6). From segment I, commutator common bar A of the units denomination, I segment, contacts R24a (shifted), g contacts of relay RI3 (normal), 9 contacts of relay RI4 (shifted), relay R5 to line 6, thus energizing relay R5.
Thus, at the end of the sensing commutator movement, the following relays have been energized: R2I, RI8, R20, RI5, RI2, RI4 and R5. These relays close their related q contacts (Fig. 1a) to energize the holding coils R2 IH, RI 8H, etc. In addition, the relays R21, R26, R25 and R24 are energized being in series with R2I, RI8, RI5 and RI2, respectively. The hold circuits run in parallel from line I through cam contacts C3 which are closed during the whole of the translating operation, and relay contacts R2811, in parallel, the closed q contacts, relay coils to line 6. A further circuit is made from line I through cam contacts C3, contacts R51) (shifted), relay coil R411 to line 6, to energize relay R4.
The circuits now set up by the combination of the accumulator commutator settings and the shifted relay contacts described in the preceding paragraph allow the reading out of the quotient of 16307 divided by 6 on the second conversion cycle in complement form to effect the required subtraction. The complementary number is read into the accumulator by the circuits described hereinafter for the second conversion cycle.
At the beginning of the second cycle, relay RI I is deenergized by the opening of cam contacts (not shown) and relay R2 (Fig. 1) is energized by the closure of cam contacts (not shown). Through contacts R2a (shifted), a circuit is made to energize relay RI which shifts the related contacts RIa to RIe.
In Fig. 1a is shown an emitter EI, well known in the art, which provides impulses at digital times on the related lines. At 9" time, a circuit will be made as follows: from line I (Fig. 1a)..
brush of emitter El, segment 9, segment I of commutator C of the tens thousands denomination, common bar. contacts RIe (shifted) (Fig. 1), accumulator magnet RIO of the ten thousands denomination to line 6.
Further circuits at the corresponding digit times will be made:
(1). From emitter segment I, contacts R230 (normal) (Fig. 1a), contacts R2Ic (shifted), contacts R22b (normal), contacts R2 Ib (shifted), segment 6 of commutator C of the thousands denomination, common bar of commutator C, contacts RId (shifted), accumulator magnet R9- to line 6.
(2). From emitter segment 2, 0 contacts of relay R20 (shifted) (Fig. 1), contacts RI8c (shifted), segment 3 of commutator C of the hundreds denomination, common bar of commutator C, contacts RIc (shifted), accumulator magnet R8 to line 6.
(3). From emitter segment 8, b contacts of relay RII (normal) (Fig. 1), contacts Rl5d (shifted), segment 0 of commutator C of the tens denomination, common bar of commutator C, contacts RIb (shifted), accumulator magnet R1 to line 6.
(4). From emitter segment 2, contacts R40 (shifted) (Fig. 1), 0 contacts of relay RI4 (shifted), contacts RI2c (shifted), contacts RI3b (normal), contacts RI2!) (shifted), segment I of commutator B of the units denomination, contacts RIa (shifted), accumulator magnet R6 to line 6. It was previously noted that two relays are provided for controlling the pence readout when this is tenpence or elevenpence. these relays is relay R4, which increases the quotient digit by one when the a to f contacts of relay R4 are shifted. For example, the connection from the 1 segment of commutator B of the units denomination is made to emitter line 3 when relay R4 is not energized and to line 2 when relay R4 is energized. The circuit is traced from the I segment of commutator B, through contacts RI2b (shifted), contacts Rl3b (normal), contacts RI2c (shifted) to the shifted c contacts of RI4. When relay R4 is not energized, the circuit is completed to emitter line 3. When relay R4 is energized and the 0 contacts of R4 are shifted, the circuit is completed to emitter line 2. Since this readout is in complement the true units digit would be 6 with relay R4 not energized and 7 when relay R4 is energized. The second relay is relay R5 and this, when energized, breaks the circuit for entry of the elusive one" by opening contacts R5a. Normally, when cam contacts C4 close momentarily at the end of the accumulator entry cycle, a circuit is made through contacts R5a to energize the carry magnet R3 of the units denomination and thus cause an additional entry of one.
In the present example, the complemental value read into the accumulator by the accumulator magnets being energized at appropriate digital times through the circuit network just described, is 97282. This is the complement to 9 of 2717, which is the quotient of 16307 divided by six. Thus the quotient is odd, but since the remainder is five, both relays R4 and R5 are energized and the complement of the true value of the quotient is subtracted from the original value with the elusive one carry suppressed.
The result registered in the accumulator is there- The first of 7 fore 13589 and not 13590 as would have been the case if the carry had not been suppressed.
At the beginning of the third conversion cycle, due to the action of the related cam contacts (not shown), relay R2 is deenergized and relay R29 (Fig. 1b) is energized. Contacts R29a close and set up a series of circuits from line I via contacts R2911:
(1). To relay R28 and line ii. The ener'gization of relay R28 opens contacts R28a (Fig.- la) and places the circuit to the holding coils R4H, Rl5I-I, RIZH, etc. under control of the cam contacts C3. These contacts break at the end of the third conversion cycle and thus deenergize all the aforementioned relays.
(2). To common bar of commutator D of the ten thousands denomination, segment I, relay RBI to line 6, thus energizing relay R3I.
(3). To common bar of commutator D of the thousands denomination, segment 3, relay R30 to line 6, thus energizing relay R30.
After the relays R30 and R3l have closed their related contacts, a series of digitally timed impulses are supplied by the emitter E2 to selectively energize the readout lines 8 to represent the sterling amount of the translated pence value, the brush of the emittter being secured to a shaft driven from the machine drive shaft through suitable gearing. From line 1, the brush of emitter E2 and the noted segments, the following circuits are made:
(1). At 6 time, to contacts Rfild (shifted), segment 3 of commutator E of the thousands denomination, common bar, to line 8 tens of pounds.
(2). At '7 time, to contacts of relay R36 (shifted), segment of the commutator E of the hundreds denomination, common bar to line 8 units of pounds.
(3). At 1 time, to segment 5 of the commutator D of the hundreds denomination, common bar to line {items of shillings.
(4). At 8 time, to segment 8 of commutator D of the tens denomination, common bar to line 8 units'of shillings.
(5). At 1 time, to contacts Rdt (shifted) to line 8 tens of pence.
(6). At 1 time, to contacts R58 (shifted), contacts R45 (shifted), segment '9 of commutator D of the units denomination, common bar to line 8-units of pence.
(7). At "0 time, to segment I of the commutator E of the ten thousands denomination, common bar to line 8 hundreds of pounds.
Thus the value 67: 18: 11d. which is the sterling equivalent of 16307 pence, has been read out on the lines 8 by digitally timed impulses selected by the circuits described. This readout may be employed to enter the value in a second accumulator, control the type selecting mechanism of a print unit, or otherwise effect a registration, in Well known manner. For the purposes of this invention a result device is shown in Fig. ID for receiving the sterling value. The result device includes a relay for each denomination of the sterling value. These relays are designated R-33, l t-34, R455, R-BS, R-3l, R38 and R39 in Fig. it).
While there have been shown and described and pointed out the fundamental novel features of the invention as applied to a preferred embodiment, it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and in its-operation may be'made by those skilled in 8 the art, without departing from the spirit of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the followin claims.
What is claimed is:
1. In a cyclically operable machine, an accumulator arranged for additive or subtractive operations having denominationally ordered elements, each element having a plurality of read out devices, means for entering a pence value in the units and higher orders of the accumulator, a dividing circuit, operable during one cycle for subtractively entering in the accumulator the nines complement of one sixth the pence value registered on the accumulator neglecting any remainder, a result device including a plurality of denominationally ordered control elements, column shift devices and control means effective during the following cycle for effecting a readout of half the value registered in the hundreds and higher orders through said column shift devices to the elements of the result device whereby the value standing in the hundreds and higher orders will be read out as the nearest units and higher denominations of pounds.
2. In a machine of the class described, a device settable to represent an amount, an impulse emitter for emitting a single series of electrical impulses, one impulse for each of the digits 1 to 9, a cyclically operable accumulator responsive to electrical impulses, said emitter being arranged to emit a single series of impulses for one cycle of operation of the accumulator, readout devices, circuit connections between the emitter and the accumulator extending through said readout devices, means for readjusting the circuit connections and effective during said cycle of the accumulator for selecting from said single series of impulses, impulses representative of five-sixths the amount standing in the accumulator, a result device, column shift devices, other readout devices, and means controlled by the other readout devices on the following cycle through said column shift devices for making a direct entry in the result device.
3. In a machine of the class described, a device settable to represent an amount, an impulse emitter for emitting a single series of electrical impulses, one impulse for each of the digits 1 to 9, a cyclically operable accumulator responsive to electrical impulses, said emitter being arranged to emit a single series of impulses for one cycle of operation of the accumulator, readout devices, circuit connections between the emitter and the accumulator extending through said readout devices, means for readjusting the circuit connections and effective during said cycle of the accumulator for selecting from said single series of impulses, impulses representative of five-sixths the amount standing in the accumulator, a result device, other readout devices, another impulse emitter for emitting another single series of electrical impulses, circuit connections between the emitter and the accumulator extending through said other readout devices, means for altering the circuit connections and effective on the following cycle for selecting from the second single series of impulses, impulses representative of the sterling equivalent of the amount originally entered in the accumulator, column shift means for shifting the denominational allocation thereof and means for making a direct entry of the sterling amount in said result device.
4. The device of claim 1, including means for reading out a l in the tens of shillings denomination when the digit in the hundreds denomination of the five sixths value is odd.
5. The device of claim 4, including means for reading out the digit standing in the tens denomination of said five sixths value as the units of shillings value.
6. The device of claim 5, including means for reading out the units digit of said five sixths value as the pence value when the one sixths value is even.
7. The device of claim 1, including means operable on the first cycle for decreasing the units digit of the one sixth value by one so as to increase the units digit of the five sixths value by one when the units digit of said one sixth value is odd, means responsive to the occurrence of a neglected remainder of four or five to prevent a decreasing of the units digit, and means for reading out the units digit of the corrected five sixths value as the pence value.
8. The device of claim 7, including means effective on the first cycle for controlling the entering of a 9 in the units order of the accumulator when the units digit of said one sixth value is odd and the neglected remainder is a four or five, and for controlling the correcting of the "9 10 readout to "10 or 11 when the neglected remainder is four or five respectively.
9. The device of claim 8, wherein the latter control means includes a pair of relays, the first of which effects an altering of the dividing circuit in a manner whereby the complement to "9 of the actual value of the one sixths value is registered in the accumulator.
10. The device of claim 9, wherein the second relay effects an altering of the dividing circuit in a manner whereby the entry of the elusive one is suppressed when the neglected remainder is five.
ALBERT J. KEEN.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,877,801 Britten Sept. 20, 1932 2,066,764 Campbell Jan. 5, 1937 2,113,612 Campbell Apr. 12, 1938 2,126,615 Campbell Aug. 9, 1938 2,399,755 Mills et a1. May 7, 1946
US188431A 1949-10-12 1950-10-04 Mechanism for converting pence amounts to sterling Expired - Lifetime US2620976A (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1877801A (en) * 1932-09-20 britten
US2066764A (en) * 1931-07-02 1937-01-05 Ibm Tabulating machine
US2113612A (en) * 1933-01-13 1938-04-12 Ibm Calculating machine
US2126615A (en) * 1935-03-26 1938-08-09 Ibm Accounting machine
US2399755A (en) * 1944-04-01 1946-05-07 Ibm Accounting mechanism

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1877801A (en) * 1932-09-20 britten
US2066764A (en) * 1931-07-02 1937-01-05 Ibm Tabulating machine
US2113612A (en) * 1933-01-13 1938-04-12 Ibm Calculating machine
US2126615A (en) * 1935-03-26 1938-08-09 Ibm Accounting machine
US2399755A (en) * 1944-04-01 1946-05-07 Ibm Accounting mechanism

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